fastdude007

I'm searching for some answers on my 2012 Jeep Grand Cherokee Laredo X. I'm very happy with this vehicle but after driving 10k this summer I have the following questions. I found the Pentarstar 3.6 V6 very sluggish between 2000 and 3000 rpm till the engine really picked up around 3500 rpm. As a result I did the following modifications. Magnaflow catback, Airaid cold air intake and a Gforce chip. Now using scan gauge in the jeep it should an approx. improvement of 30 hp. The motor runs smoother now throughout the lower rpm range and it seems to have more torque in the lower rpm range. I also feel that the 5 speed auto transmission is geared to high and the gears are too far apart. Under heavy load it seems to keep shifting up and down constantly which is very annoying, especially on in climbs. I realize I should bought the V8 instead but I didn't. In the next week I will get the vehicle dyno tested to see the real improvement since many people tell me I wasted my money and none of the modifications will improve power. So far my average mileage is 26 highway (9.2 litre) and 23 mpg city (10.5 litre per 100km) Did anyone else did any modification on their Pentastar V6? What are the results? Thank you for any feedback.

Bluemoon

I would invest in a Diablo Insport tuner - $400

I bought one for my Grand Cherokee and it gives me better performance and fuel economy.

JB RACING

You have done all the good basics to start. I think you will have more than 30 HP gain with that.
Will be interesting to know what your truck will do on the Dyno..

Dave_N

I have a 2011 JGC with the 5.7L V8 Hemi engine and it runs perfectly. It burns more fuel than the Pentastar V6, but at least I know that if I need to tow a boat, I should have plenty of power. I think the Pentastar is an ideal engine for cars like the Charger, but for a heavier SUV, the Hemi is king.

Bobber

Hi Fastdude..reading your post with interest as I am looking for a SUV for my wife. Reading your MPG, and I think something is wrong? By my calculations 9.2l = 30.65 mpg hiway and 10.5l = 26.86 mpg. That looks really good to me. Regards..............Bobber